Using a controller and and view together - sapui5

Question

I'm writing my first SAP app, and having gone through some of the tutorials, I understand that I need a controller for my view if I want it to do anything.
When I add the controllerName="./controller/login" (the controller's called 'login.controller.js'), it doesn't work, and I've tried variations of this.
The tutorials get me to copy code that uses the controller name, but they don't teach me anything about how to write the string for my own controller code.
How do I do this?
Controller code looks like this so far:
sap.ui.define([
"sap/ui/core/mvc/Controller"
], function(Controller) {
"use strict";
return Controller.extend("controller.Login", {
// controller logic goes here
});
});
and the view code looks like this:
<mvc:View
controllerName="controller.Login"
xmlns="sap.m"
xmlns:form="sap.ui.layout.form"
xmlns:mvc="sap.ui.core.mvc">
<Panel headerText="{/panelHeaderText}" class="sapUiResponsiveMargin" width="auto">
<form:SimpleForm editable="true" layout="ColumnLayout">
<Label text="User Name"/>
<Input value="{/firstName}" valueLiveUpdate="true" width="200px"/>
<Label text="Password"/>
<Input value="{/lastName}" valueLiveUpdate="true" width="200px"/>
<Button text="login" press=".onVisitHomePage"/>
</form:SimpleForm>
</Panel>
</mvc:View>
I'm going to add the .onVisitHomePage function to the controller but first I want to get this to work.

Answer 1

Like Julian Schmuckli already said you have to prefix the controller.login with your Namespace check you index.html where you initialize the sap-ui-core (see below).
<script src="resources/sap-ui-core.js" id="sap-ui-bootstrap"
data-sap-ui-theme="sap_bluecrystal" data-sap-ui-libs="sap.m"
data-sap-ui-bindingSyntax="complex" data-sap-ui-compatVersion="edge"
data-sap-ui-preload="async" data-sap-ui-async="true"
data-sap-ui-frameOptions="trusted" data-sap-ui-appCacheBuster="./"
data-sap-ui-resourceroots='{
"your.namespace": "./",
"sap.ui.demo.mock": "mockdata"
}'></script>
Here you have to take the string that is in place of the "your.namespace" and combine it with the controller.login to your.namespace.controller.login .
You have to do this in both the view and the controller file.